This is an entry into the 29th fortnightly topic challenge - Retrograde Analysis.
You're passing a bridge table when one of the players (South) is called away suddenly. He gives you his hand and says "There are no trumps. You need all seven tricks. It's your lead." before disappearing. You find that you're declarer, South, with these hands:
♠ K2 ♡ Q2 ♢ 2 ♣ 32 N W E S ♠ A3 ♡ AJ ♢ A3 ♣ A
The other players refuse to tell you anything about the play of the first six tricks. You lead your aces, and both defenders follow suit.
How do you play the last three tricks?
This problem is a variation, by me, of one by Jonathan Mestel.